The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 16, 2003
Filed:
Nov. 30, 2000
Thomas E. Schiltz, Colorado Springs, CO (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
A double balanced mixer circuit receives an input signal (RF ) at first input terminals ( ), supplying that signal to the primary side of a transformer ( ). The secondary side of the transformer ( ) is coupled to the bases of transistors ( and ) that supply the tail currents to a pair of differential transistors. The center tap of transformer ( ) receives a voltage (V ) that keeps the transistors ( and ) biased in their linear regions. A capacitor ( ) provides an AC ground at the center tap point of the transformer ( ). The first differential transistor pair ( and ) and the second differential transistor pair ( and ) receive a differential signal (LO) at second input terminals A differential signal IF down-converted in frequency from the RF frequency range to the IF frequency range is supplied at output terminals ( ).